click for bigger image click for bigger image It is also the only fixed focal length EF lens that employs Canon's Micro USM for autofocus. The Micro USM was originally designed for use in Canon's budget-priced EF zoom lenses such as the EF28-80mm f/3.5-5.6 IV USM and EF 75-300mm f/4.5-5.6 IS USM and the AF motor for this 50mm lens is also the only Micro USM with built-in full-time mechanical manual focusing ring. Both of today's beginners and amateur photographers may not realise the importance of the 50mm standard lens, preferably to buy their first 35mm SLR cameras, whether AF or manual-focus types, usually in kit forms complete with either a 35-70mm or 28-80mm zoom lens. The 50mm lens remains one of my favourite lens and I considered it to be one of the most important lenses to carry around on assignments, even if my camera bag is already full with a couple of high-performance fast aperture zoom lenses. click for bigger image click for bigger image The 50mm lens is also the fastest lens that I have in my personal EOS/EF lens system. Its f/1.4 maximum aperture means that I am able to shoot using slower speed films of ISO 50 or 64 even when the light level is getting lower. And it is lightweight, weighing at only 290 grams, light enough for handheld shooting with slower films even down to using a shutter speed of 1/8 sec. provided you are able to steadily hand held the camera. The AF response too, it is fast and highly accurate, which is important if you have to snap candid shots via available light without the subjects being aware that you are snapping their pictures. << Back to Main . 1 . 2 . 3 . 4 . 5 .